Method and apparatus for packaging with stationary inner mandrel for forming flat bottom package



Dec. 1, 1970 w. c. LEASURE 3,543,463

' METHOD AND APPARATUS FOR PACKAGING WITH STATIONARY.

INNER MANDREL FOR FORMING FLAT BOTTOM PACKAGE Filed Dec. 19, 1967 V 2 Sheets-Sheet 1 T w ml m mi N 6E w ml ATTORNEYS Dec. 1, 1970 w. c. LEASURE 3 5 METHOD AND APPARATUS FOR PACKAGING WITH STATIONARY INNER MANDREL FOR FORMING FLAT BOTTOM PACKAGE Fi led Dec. 19, 1967 2 Sheets+ h 2 U N N .n N a: Q) E INVENTOR WILLIAM C. LEASURE ATTORNEYS StacS 3,543,468 METHOD AND APPARATUS FOR PACKAGING WITH STATIONARY INNER MANDREL FOR FORMING FLAT BOTTOM PACKAGE William C. Leasure, Houston, Tex., assignor to Mira-Pak, Inc., Houston, Tex. Filed Dec. 19, 1967, Ser. No. 691,870

Int. Cl. B65b 9/00 U.S. Cl. 53-28 17 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND-FIELD OF THE INVENTION This invention relates to packaging and more particularly to a method and apparatus for forming a flat bottom package on a form fill and seal type packaging machine having a former which reciprocates with respect to stationary sealing jaws to draw film over the former.

BACKGROUNDDESCRIPTION OF THE PRIOR ART In my prior Patent 2,969,627, there is described a method and apparatus for packaging wherein the former which shapes the strip packaging film into tubular form reciprocates with respect to sealing jaws which move into and out of engagement with the packaging film in a horizontal plane. When the sealing jaws move into engagement with the film to form a package end seal the former is moved away from the jaws to draw additional film over the former. The sealing jaws are released and the former is moved towards the jaws to pass the film between the jaws. 'Ihe jaws are then brought together to form the other package end seal.

A package formed as above described is a pillow type package which has the disadvantage of not being able to stand upright. Thus, in the prior art there has been a need for a method and apparatus for forming a flat bottom bag on form fill and seal packaging machinery.

SUMMARY OF THE INVENTION The present invention provides a method and apparatus for forming a flat bottom package on form fill and seal packaging machinery of the type shown in my prior Pat. 2,969,627.

A packaging machine such as shown in Pat. 2,969,627 is provided with a stationary inner mandrel which extends through the former and into the tubular shaped packaging film. The lower end of the mandrel is shaped to form a fiat bottom on a package end when the package end is drawn into close contact with the end of the mandrel. An external platen may be provided to fold the transverse end seal of the package against the fiat bottom of the package to further shape the bottom of the package.

According to the presently disclosed method of packaging the sealing jaws are first brought together on the tubular shaped packaging film to form one package end seal. The former is moved upwardly away from the jaws to draw more film over the former. When an additional 3,543,468 Patented Dec. l, 1970 package length of film is drawn over the former, the sealing jaws are released but the former continues its upward movement until the package end seal is brought into contact with the end of the mandrel. The end of the mandrel is shaped to cause the package end to be flattened with the end seal projecting outwardly from the flat bottom. If desired an external platen may be brought into contact with this end seal to flatten it against the bottom. Adhesive or heat sealing means may be utilized to retain the end seal in this position.

When the shaping of the package end has been completed, filling of the package with product may occur and the external platen is removed and the former is moved downwardly towards the sealing jaws so as to pass the flat bottom of the open topped package between the sealing jaws. If desired a stripping operation such as disclosed in my prior Pat. 3,027,695 may then take place. The sealing jaws are again brought together to form the top of the package upon which the fiat bottom has been formed and the bottom of the next succeeding package.

It is an object of this invention to provide a new method and apparatus for forming a fiat bottom on a tubular package on form, fill and seal packaging machinery.

It is another object of this invention to provide a packaging method and apparatus of the type wherein a continuous web of material is formed into a tubular length of material employing a stationary mandrel for forming a fiat bottom package.

Other objects and the attendent advantages of the present invention will become apparent from the detailed description to follow together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS There follows a detailed description of the preferred embodiment of the present invention together with accompanying drawings. However, it is to be understood that the invention is capable of numerous modifications and variations apparent to those skilled in the art without departing from the spirit and scope of the invention.

In the drawings:

FIGS. 1 through 6, inclusive, are diagrammatic drawings showing the sequence of operation of the present invention in connection with the packaging of a product.

FIG. 7 is a schematic perspective view illustrating the position shown diagrammatically in FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED In the accompanying drawings like numerals are employed to designate like parts throughout.

Referring to FIG. 1, a continuous web of material 11 is fed from a supply roll 10 over rollers 12, 13 and 14 and over roller 15 which is connected to a former 16 for movement therewith. The former 16 then forms the continuous web of material 11 into a tubular length of material 18, the opposing edges of the web being connected together by a longitudinal sealing means 17. The roller 15, the former 16 and the longitudinal sealing means 17 are reciprocated vertically by the apparatus shown in the Leasure Pat. No. 2,969,627. Also, the former 16 may be of the type shown in FIGS. 13 and 14 of the said Leasure patent. A pair of sealing jaws 22a and 22b are provided for forming a transverse seal across the tubular lengths 18. These sealing jaws further include cooperating knife and slot means 23a and 23b for severing a completed package after its top seal has been formed. The sealing jaws may also include stripper plates as shown in the Leasure Pat. No. 3,027,695.

The apparatus further includes a hollow mandrel 19 having a funnel 21 located at the upper end thereof for receiving a product and delivering the same into the hollow mandrel. The mandrel further includes a lower end 20.

The shape of the bottom of the mandrel determines the configuration of the finished package. For example, if one desired a round flat bottom then one would employ a round mandrel. However, in a preferred embodiment of the invention, the mandrel will have a generally rectangular cross-section with two opposing sides having slightly indented V shaped grooves for cooperating with gusseting bars 35, in a manner to be described in greater detail below for forming a gusseted package.

At the lower end of the apparatus there is provided a platen 30 including a connecting rod 31 rigidly connected thereto, the combination of platen 30 and connecting rod 31 being mounted for pivotal movement about a stationary pivot axis 32. Connecting rod 31 is in turn pivotally connected to a piston rod 33 which is in turn connected to a double acting piston in the cylinder 34. Thus, by moving the piston to the right or the left, the platen 30 can be raised or lowered, respectively.

The operation of the invention is as follows. The film passes over the former and is shaped into tubular form. The longitudinal sealing means 17 seals the longitudinal edges of the film together. In FIG. 1, the sealing jaws 22a and 2212 are forming a transverse seal which will constitute the top of package A and the bottom of package B. In FIG. 2, while the sealing jaws are still in engagement with the tubular length 18, the former 16 is moved upwardly to provide an additional length of tubular material which will subsequently form package C. In FIG. 3 the package A has been separated. Between FIGS. 3 and 4 the former has then been moved upwardly so that the lower end of package B engages the lower end of the mandrel 19. This action will tend to flatten the bot tom of package B. It may be desirable to fold the lower transverse seal against the flat bottom of package B. For this purpose the piston in cylinder 34 is moved to the right to raise the platen thereby pressing the lower end of package B against the lower end of the mandrel 20. Product may be introduced into the funnel 21 as soon as the bottom of package B has engaged the bottom 20 0f the mandrel 19. After the bottom of package B has been completely formed, the platen 30 is lowered after which the former is also lowered to place the length of material constituting package B to a level below that of the sealing jaws 22a and 22b. The sealing jaws are then operated to close the package B and form the bottom seal of package C thereby attaining the position of FIG. 1 after which the cycle is repeated.

The method and apparatus of the present invention may be employed in the production of either a pillow type package or a gusseted type package. In the production of a pillow type package the two ends of the lower seal would project laterally after the said lower seal has been folded up to the package. Suitable means (not shown) may be employed for folding these ends up to and attaching them against the sides of the formed package. Alternatively, means (not shown) may be employed for folding these ends under the package before the package engages the flat surface of platen 30.

FIG. 7 illustrates the shape of the mandrel and the procedure for forming a gussetted type package. The upper end portion 19 of the mandrel adjacent the funnel 21 and extending through the former is of a shape so that it passes through the former with clearance and does not interfere with the reciprocatory movement of the former. The end portion 20 of the mandrel is generally rectangular of the shape to give the package the desired configuration. The sides of the end portion 20 include a pair of V shaped indentations to form gussets in the tubular shaped packag ing film. V shaped gusseting bar then push the sides of the tubular length 18 inwardly to form the gussets. The sealing jaws 22a and 2212 then form the transverse seal between packages B and C thereby permanently forming the gussets in the vicinity of the said transverse seal. As illustrated, the longitudinal seal would be located on the front or back of the package. However, it is possible to rotate the gusset forming means and transverse sealing jaws relative to the former so that the longitudinal seal would be located on the side of the package and formed into one of the gussets. One advantage of this would be to leave the front and back of the package free for the advertising message.

Although preferred embodiments of the invention have been illustrated and described in considerable detail, it should be understood that the invention is capable of numerous modifications and variations apparent to those skilled in the art without departing from the spirit and scope of the invention as defined in the claims.

I claim:

1. A method of packaging comprising forming a continuous web of material into a tubular length of material by passing the web over a former and moving the formed tubular length of material downwardly, forming a package closing end seal across the tubular length of material, and flattening the end of the tubular length of material remote from the former by raising the former so that it carries the tubular length of material upwardly until the end of the inside of the tubular length of material remote from the former engages a stationary member located therein so that said stationary member applies pressure to the interior of the tubular length of material as it is being raised by the former to flatten the bottom of the tubular length of material, and hence form a flat package bottom.

2. The method of claim 1 wherein the said stationary member is a hollow stationary mandrel extending vertically into the tubular length of material for introducing product therein.

3. A packaging apparatus comprising a former means for forming a continuous web of material into a tubular length of material by passing the web over the former, and means for moving the former tubular length of material downwardly relative to the former, sealing means for forming package closing and seals across the tubular length of material, and flattening means for flattening the end of the tubular length of material remote from the former, said flattening means comprising a stationary member located inside the tubular length of material and means for raising the former so that it raises the tubular length of material until the inside thereof engages the stationary member such that the said stationary member applies pressure to the interior of the tubular length of material as it is being raised upwardly by the former, thereby forming the said flattened bottom of the package.

4. The method of claim 2 wherein the step of flattening the remote end of the tubular length of material includes pressing the said remote end between the said end of the mandrel and a flat platen surface to press the last formed end seal fiat against the said remote end of the tubular length of material, thereby forming the said fiattened end.

5.. The method of claim 4 wherein the said end seals are formed by sealing means comprising a pair of opposing sealing jaws reciprocal towards each other to an operative position to form said seals, and away from each other to an inoperative position, the sealing jaws being prevented from moving in the direction of movement of the former, and wherein the step of moving the former comprises moving the said former so that the remote end of the tubular length of material moves to a point on the side of the sealing jaws closest to the former, said flat platen surface being adapted to be located at said point.

6. The method of claim 5 wherein the former is moved away from the sealing jaws to form an additional length of material as the tubular length of material is held by the sealing jaws, after which the sealing jaws are moved to the inoperative position and the former is moved so that the said remote end engages the said end of the stationary mandrel, and the flat platen surface engages the remote end of the package to complete the said flattened end.

7. The method of claim 6 wherein after the completion of the said flattened end, the former moves the length of tubular material below the sealing jaws and the sealing jaws move towards each other to form a top seal to close the package which includes the previously formed flat bottom.

8. The method of claim 2 including the step of feeding a product through the mandrel to a package, the bottom of which will be constituted by said remote end, such that product reaches the said remote end only after it has been engaged by the stationary mandrel.

9. The method of claim 8 including the step of forming gussets in opposite sides of the tubular length of material.

10. The method of claim 9 wherein the mandrel is generally rectangular in cross-section and includes a pair of V shaped grooves extending longitudinally of said mandrel on opposing sides thereof, and wherein the step of forming gussets in the tubular length material comprises pressing gusset bars against the tubular length of material thereby urging the same against the said grooves.

11. The method of claim 10 wherein the step of fiattening the remote end of the tubular length of material includes pressing the said remote end between the end of the mandrel and a flat platen surface to press the last formed end seal flat against the said remote end of the tubular length of material, thereby forming the completed flattened end.

12. The apparatus of claim 3 wherein the said member is a hollow stationary mandrel extending vertically into the tubular length of material for introducing product into the tubular length of material.

13. The apparatus of claim 12 wherein the lower end of the mandrel has a cross-sectional area slightly less than the cross-sectional area of the tubular length of material.

14. The apparatus of claim 13 including a platen having a flat surface movable into the path of movement of the remote end near the said lower end of the mandrel so that the said end of the mandrel can press the said remote end of the tubular length of material against the said fiat platen surface.

15. The apparatus of claim 13 wherein said sealing means are prevented from moving in the direction of movement of the former.

16. The apparatus of claim 13 wherein the cross-sectional area of the mandrel is generally rectangular.

17. The apparatus of claim 16 wherein opposing sides of the mandrel include indented V shaped grooves, and gusset bars are provided for pressing the tubular length of material into the said grooves to form the said gussets.

References Cited UNITED STATES PATENTS 12/1965 Holfmann et al. 53l82 8/1966 Wallsten 53-28 US. Cl. X.R. 53--180 

